Peat press

ABSTRACT

A press for dewatering peat having an endless belt made of a flexible absorbent material on a central portion of which peat is continuously fed and side portions of the belt then folded and lapped over the peat for passage in folded condition between a set of press rolls, the rolls being arranged so that an upper roll of the set is in advance of a lower roll so that travelling belt passes upwards through the nip. A scraper below the lower run of the belt opens the belt and scrapes the dried peat therefrom.

United States Patent 1191 1111 3,805,692 Fischer 1 Apr. 23, 1974 [5 PEAT PRESS 502,523 8/1893 Lockstaedt 100 120 X [75] Inventor: Uwe Michael Fischer, Chilliwack 358,989 3/1887 Sanor 100/120 x British Columbia, Canada [73] Assignee: Fischer Holdings Ltd., British Columbia, Canada [22] Filed: Sept. 5, 1972 [21] Appl. No.: 286,168

[52] U.S. Cl. 100/120 [51] Int. Cl B301) 9/24 [58] Field of Search 100/36, 110, 112, 116, 100/118,119,120,122,144,151,152,153, 154, 208, 211, 212, 298

[56] References Cited UNITED STATES PATENTS 457,217 8/1891 Rohrer 100/120 X Primary Examiner-Leon G. Machlin Attorney, Agent, or Firm-Carver and Company ABSTRACT A press for dewatering peat having an endless belt made of a flexible absorbent material on a central portion of which peat is continuously fed and side portions of the belt then folded and lapped over the peat for passage in folded condition between a set of press rolls, the rolls being arranged so that an upper roll of the set is in advance of a lower roll so that travelling belt passes upwards through the nip. A scraper below the lower run of the belt opens the belt and scrapes the dried peat therefrom.

4 Claims, 6 Drawing Figures DATENTEUAPR 23 I974 SHEET 1 [IF 3 mosxssaz "PRINTED APR 2 3 I974 SHLH 2 OF 3 NwN BACKGROUND OF THE INVENTION l. Field of the Invention This invention relates to apparatus for mechanically reducing the water content of peat;

2. Prior Art Newly developed processes and methods for treating peat for use as an oil absorbent and in coking processes required that the peat be dried to a water content of approximately ten percent by weight of the peat. The process involves mechanical water reduction followed by screening to separate fibre and peat particles, the fibre and the particles then separately being thermically dried to the required water content.

Known mechanical dewatering apparatus do not remove sufficient water from raw peat to enable a separation of peat fines and fibres prior to drying and consequently cause relatively high power requirements for thermically drying peatto the required moisture content.

SUMMARY OF THE INVENTION The present invention provides a press for mechanically drying peat to a point wherein the water content of peat is approximately 75 percent by weight. The peat fines and fibres can be thus easily separated. Further, power consumption for thermically drying peat to required moisture content is reduced.

The peat press of the present invention includes an endless travelling belt of absorbent material on an upper run of which raw peat to be dried is continuously fed. Side edge portions of the belt are then folded over the peat. At least one pair of press rolls is provided through which the folded belt is passed for continuously squeezing water from the peat. A scraper is adapted to extend into a lower run of the belt to scrape the peat therefrom. The press rolls are arranged so that an upper roll is in advance of a lower roll so that the belt travels upwards through the nip between the rolls.

A detail description following, related to the drawings, gives exemplification of preferred embodiment of the invention which however, is capable of expression in structure other than that described and illustrated.

DESCRIPTION OF THE DRAWINGS DETAILED DESCRIPTION Referring to the drawings and in particular to FIGS. 1 and 2, the peat press, generally has a frame 11 having vertical posts 12 and transversely spaced horizontal beams 13-13. A pair of rollers 14 and 15 are mounted at the advance and trailing ends 16 and 17, respectively, of the frame. A plurality of transverse supporting rollers, severally 18, are mounted between the beams 13-13 and extend between the advance end of peat press in accordance portion of the inventhe frame and a pressing assembly supporting framework, generally 19 adjacent the trailing end of the frame. The framework 19 having two pairs of longitudinally spaced sloped members 21 and 22, one member of each pair being shown in FIG. 1.

The framework 19 supports two pressure roll pairs 23 and 24. The lowermost roll 23.1 of the press roll pair 23 is mounted on a drive shaft 25 which is suitably journalled for rotation between the beams 1313 as is the lowermost roll 24.1 of the press roll pair 24.

The uppermost roll 23.2 of the pair 23 and the uppermost roll 24.2 of the pair 24 are mounted on drive shafts 26 and 27, respectively, which are movable longitudinally of the sloped members 21 and 22 away from and towards the lowermost rolls. As seen in FIG. 5, one end of the drive shaft 26 extends through a slot 26.1 which extends longitudinally of the sloped member 21 and is mounted for rotation in a bearing 28 slidable longitudinally of the sloped member 21 in guides 29. A rod 31 connected to the bearing 28 extends through a bracket 32 and is threaded to receive a nut 33 which can be tightened down against a compression spring 34 which extends between the bracket 31 and a pressure plate 35 which is moved by operationof a nut. The opposite end of the drive shaft 26 is similarly supported. Pressure of the upper roll 23.2 against the lower roll 23.1 can be adjusted by suitable tensioning the compression spring 34. The press roll 24.2 is spring pressed against the roll 24.1 by way of an arrangement similar to that described with regard to, the roll 23.2. Drive shafts of the rolls of all pairs carry sprockets, severally 37, which are drivingly connected through roller chains, severally, 38 to a drive sprocket 39 of a reductiongear 41 mounted on the frame 19 and driven by a suitable electric motor 42. Direction of rotation of the pressure rolls is shown by the arrows 44.

The press 10 has a travelling belt 51 which passes over the rolls 15 and 14 and between the nips of the press rolls. The upper run of the belt is supported by the supporting rolls 18. The belt is made of a spongy absorbentmater'ial, suitably a flexible Polyether Polyurethane and is sufficiently flexible to enable it to be folded lengthwise, as seen in FIG. 4 with side edge portions 51.1 abutting each other over a central carrying portion 51.2. Side edges of the belt are bevelled so as to provide a smooth overlapped joint.

A trough 52, see FIG. 1 is mounted on brackets 53 forming part of the frame 11 and extends beneath the press roll pairs between the upper and lower runs of the belt. The trough has a drainpipe 53.1 and wipers 53.2 which contact the press rolls 23.1 and 24.1.

A hopper 54 is suspended above the upper run of the belt in advance of the press roll pairs on frame members 55. The hopper has a lower rectangular chute 56, a lower edge 57 of which is spaced above the belt a distance D suitably about 2 inches, FIG. 3. The belt is normally in a folded condition, as shown in FIG. 4, for passage through the nips of the press rolls around the advance and trailing rollers 14 and 15.

The belt is opened see FIGS. 1 and 3 for passage beneath the hopper the side edge portions 51.1 passing on opposite sides of the chute 56. Vertical rollers 59-59 mounted on the beams l3--l3 of the frame 1 l 5 on opposite sides of the chute maintain the side edge \portion of the belt against the chute walls. A pair of horizontally disposed closing rollers 61-61, see FIGS. 1 and 2 are mounted on the frame 11 following the hopper for refolding the belt. Guide roller pairs 62 and 63 are mounted on the frame in advance of and following the hopper, the rollers of each pair being spaced apart a distance equal to the width of the belt in the folded condition. A hold-down roller 64 is mounted on a bracket 65 secured to the chute of the hopper for engaging and holding the carrying portion 31.2 of the belt against the supporting rollers 18 as the belt passes beneath the hopper. A scraper 66, see FIGS. l and 6, is mounted on a transverse frame member 67 below the lower run of the belt. The scraper is U-shaped and extends upward into and opens the belt.

OPERATION In operation of the peat press, peat is fed into the hopper in a shredded condition, that is, free of lumps, so that it feeds continuously and in an even layer onto the central load carrying portion of the belt thickness of the peat layer being determined by the distance between the lower edge of the hopper and the belt. The belt automatically returns to a folded condition to enclose the peat for passage through the press rolls.

Water squeezed from the peat is collected in the trough and is discharged to the side through the drainpipe. The peat is then automatically removed from the belt by the scraper.

During passage of the loaded belts through the press rolls most of the water falls forwardly of the rolls due to the relative position of the upper and lower rolls of each pair. The uppermost rolls of each pair is in advance of the lower rolls so that the belt has to travel up wardly through the nips between the roll pairs. A certain amount of water is squeezed out onto the lower roller to the side of the belt, however, upon passage through the nips any free water that is carried by the lower roller and which otherwise might be absorbed by the mechanically dried peat is absorbed by the belt. The porous belt also acts as a filter retaining the peat fines which are removed by thescraper for further treatment.

I claim:

1. A press for mechanically reducing water content of peat including:

a. an endless flexible belt, formed of an absorbent material,

b. a supporting frame in which the belt is mounted for travel and being disposed so that the belt has an upper and a lower run, the belt being normally disposed in a folded condition with side edge portions folded over a central carrying portion,

c. the side portions having bevelled side edges to provide a smooth overlapped joint when the belt is folded,

d. at least one pair of driven press rolls providing a nip through which the upper run of the folded belt passes,

e. feed means in advance of the press rolls for opening the belt and continuously feeding a layer of peat on the central carrying portion,

f. means following the feed means for returning the belt to a folded condition over the peat,

g. means at the press roll pairs and disposed between the upper and lower run of the belt for preventing water squeezed from the peat from flowing onto the lower run-of the belt,

h. a scraper disposed below the belt lower run for opening the belt and scraping the peat therefrom.

2. A press'as claimed in claim 1 in which thepress roll pair has an upper roll in advance of a lower roll so that the belt travels upwardly through the nip between the rolls.

3. A press as claimed in claim 1 in which the material forming the belt is a flexible Polyether Polyurethane.

4. A press as claimed in claim 1 in which the means for opening and feeding peat onto the belt includes a hopper having a chute depending therefrom, the chute having a lower edge spaced above the load carrying central portion of the belt and a pair of vertically arranged rolls, on opposite sides of, and spaced from the sidewalls of the chute for maintaining side edge portions of the belt in vertically upstanding positions as the belt passes beneath the chute.

l '0 il! 1k 

1. A press for mechanically reducing water content of peat including: a. an endless flexible belt, formed of an absorbent material, b. a supporting frame in which the belt is mounted for travel and being disposed so that the belt has an upper and a lower run, the belt being normally disposed in a folded condition with side edge portions folded over a central carrying portion, c. the side portions having bevelled side edges to provide a smooth overlapped joint when the belt is folded, d. at least one pair of driven press rolls providing a nip through which the upper run of the folded belt passes, e. feed means in advance of the press rolls for opening the belt and continuously feeding a layer of peat on the central carrying portion, f. means following the feed means for returning the belt to a folded condition over the peat, g. means at the press roll pairs and disposed between the upper and lower run of the belt for preventing water squeezed from the peat from flowing onto the lower run of the belt, h. a scraper disposed below the belt lower run for opening the belt and scraping the peat therefrom.
 2. A press as claimed in claim 1 in which the press roll pair has an upper roll in advance of a lower roll so that the belt travels upwardly through the nip between the rolls.
 3. A press as claimed in claim 1 in which the material forming the belt is a flexible Polyether Polyurethane.
 4. A press as claimed in claim 1 in which the means for opening and feeding peat onto the belt includes a hopper having a chute depending therefrom, the chute having a lower edge spaced above the load carrying central portion of the belt and a pair of vertically arranged rolls, on opposite sides of, and spaced from the sidewalls of the chute for maintaining side edge portions of the belt in vertically upstanding positions as the belt passes beneath the chute. 